Yadav, a local of Balasaghat, Dhanusha, is also the chairperson of Terai Ekata Parishad Party (Underground). [break]
Police arrested him on Wednesday following a tip off that he was wandering around Dhangadhi.
A group of 15 people including Yadav had ruthlessly murdered Singh, a journalist with Radio Today, at her rented room in Janakpur about six years ago.
Yadav is also accused of killing Laxmi Kanta Rai of Dhanusha and Kishori Yadav of Ramadaina VDC.
Late journalist Uma Singh remembered